Switch-cord plug.



.PATENTED APR. 2 8, 1908.

E. L. SMITH.

SWITCH CORD PLUG.

APPLICATION FILED $321.1. 1906.

- W/ TN E SSE S ATTORNEY-5' EUGENE LAMAR SMITH, OF OAK CLIFF, TEXAS, ASSIGNOR OF TWO-THIRDS TO GEORGE F.

- GHILDRES S, OF WILLS POINT, TEXAS.

SWITCH-CORD PLUG.

Specification of Letters Patent.

Patented April 2a, 1908.

T n all whom it may concern:

Be it known that I, EUGENE LAMAR SMITH, a citizen of the United States, and a resident of Oak Cliff, in the county of Dallas and State of Texas, have invented a new and Improved Switch-(lord Plug, of which. the following is a full, clear, and exact description.

This invention relates to a new and improved plug adapted to be attached to cords and used in connection with the common form of telephone switchboard, and comprises means whereby the plug may 'beinserted within a vertical switchboard and the cord relieved from all strain due to its bending at a point at which it is attached to the plug.

My improved plug is made of'two parts secured together by a ball and socket, joined so that when one part of the plug is inserted in a Vertical switchboard the other part of the plug may turn at an angle without breaking the connection or straining the wire. By this improved joint the one portion of the plug may be rotated a short distancein respect to the other, so that the cord maybe relieved of strain due to a slight twisting as the plug is inserted within the switchboard.

Reference is to be had to the accompanying drawings forming a part of this specification, in which similar characters of reference indicate corresponding parts in all the figures, in which Figure 1 is a side elevation of my complete plug having a portion of the cord attached thereto; Fig. 2 is an enlarged central longitu-.

dinal section through -my improved plug; Fig. 3 is an enlarged side elevation of the iarts constituting the socket;; Fig. 4 is an enlarged central longitudinal section throu h the socket member with one terminal of t e lug attached thereto; and Fig. 5 is an enlhrged cross section substantially on the line 55 of Fig. 2.

My improved plug may be made of any suitable esign to accommodate it to the different designs of switchboards now inuse, and the terminals of the plug may be arranged in many different manners, but the plug substantially comprises two members secured together by a ball and socket'joint, and in the specific form of my invention which I have illustrated in the drawings, the socket member is carried bythe portion of the plug'inserted. within the switchboard,

while the ball portion is carried on theend' of the cord.

The ball 1 is formed integral with the head 2 on the end of a cord and is separated therefrom by a short hollow neck 3: The head-2 may be secured to the ends of the wires of the cord 4 in any suitable manner, as forinstance, extending each of the Wires through insulating casings 5 and 6 and connecting one of these wires to the head by a suitable terminal connection 7, while the other is entirely insulated from the head and adapted tobe secured to thewire extending to the tip of the plug, as, will be hereinafter described. The' socket member of the plug is formed from a hollow cylinder s lit longitudinally into two parts 8 and 9 an provided with a smoothly polished socket 10, at one end thereof, ada ed to exactly fit the outer surface of the ball 1 The two partsS and 9 are rigidly held toof which fit within countersunk openings so If desired, a notch or lug 13 may be provided on that no part projects beyondthe surface.

one of the parts adapted to fit intoa similarly shaped recess on the other part and keep the two in perfect alinement. o

Secured to the end of the socket member at the end opposite to the socket, is a short tube-14, through the edges of which extend the bolts 12 so that the tube is rigidly held in place; but the bolts 12 do not extend through the inner surface of this tube. Within the tube 14 is a bar 15 separated thereform by suitable insulating material 16 and terminating within the socket member in the form of an enlarged head 17, which also is insulated from thesocket member. The rod 15 has a tip 18 secured to its outer end by means of a screw 19, but the tip' and screw are carefully insulated from the tube 14. An insulated conductor connects the enlarged head 17 with the terminal of the wire 5 within the head and secured to the cord, and this wire asses through the hollow ball 1 and neck 3, lioth of which are rounded on their inner sides so that no sharpedges are present to injure the insulated wire or destroy the insulation. The socket member has a portion (i one of the parts cut away to form an opening switchboard b v ner wall of the socket with a recess 23 adapted to receive a pin or stud 24 carried by the ball. The size of the recess may be varied at will and'theconta'ct of the pin or stud with the side of the" recess will prevent further movement ofthe ball and socket in respect to each other. I

The wire 5 of the cord is connected to the means of the insulated terminal within t e head, the wire 20, head 17, rod 15, screw .19 andtip 18, while the wire '6 of the cord is in electrical'contact with the head 2 andthe current passes through. the parts forming the ball. and socket and through the remainder of the socket member to the .tube 14. Upon inserting the plug withinthe sv'vitchboard, the .tip 18 and tube 14 contact with the two terminals within the switchboard in the ordinary. manner.

It is evident that the particular form of the terminals and the specific structure of the plug does not constitute the essence of my in vent1on,,-as various changes maybe made in. the details withoutdepartijng from the spirit of the'invention. I

Having thus described my' invention, I

claim as new and desire'to secure by Letters Patent:

' 1. A device of the class described, comprising a switch cord and a switch cord plug movable in respectv to each other, the switch cord being provided with a hollow ball secured thereto by a hollow neck and the switch cord plug being provided with a socket adapted to receive said ball, said socket.

member being formed of two sections rigidly secured together to holdthe ball within the socket, a cylindrical casing inclosing said sections, and a wire extending through said hollow ball and socket and insulated from both and one of said sections being rovided with an opening adjacent the end of said wire and normally covered by said casing.

2. A device of the class described, comprising .a switch cord and a switch cord plug, the switch cord being provided with a hollow ball secured thereto by a hollow neck and the switch cord plug being provided with asocket adapted to receive said ball, said plug being formed of two semi-cylindrical members rigidly secured together to hold the ball within said socket, and a cylindrical casing surrounding said plug;

3. A device of the class described, comprising two members movable in respect to ach' other, a hollow ball carried by one of said members, a socket carried by the other of said membersand adapted to receive said ball, said socket member being formed of two sections secured together to retain the ball within the socket and one of said sections having an opening thereln, a casmg mclosuig said sections and normally covering said opening, and a wire extending through said ball and socket and terminating within said socket member adjacent the said opening.

In testimony whereof I'have signed my "name to this specification in the presence of two subscribing witnesses.

EUGENE LAMAR SMITH.

Witnesses:

B. F. SMITH, LEONARD JOHNES. 

